Has anybody flown the Backcountry Cub slats ? They advertise them for $4000.00 and say they will bolt on any cub wing. I'm building a PA-12 and need to rebuild the wings, add flaps and move the ailerons so I'm wondering if this might be something to include. The add said the stall speed is reduced by 30-50%, just wondering how close that would bring you to losing the tail . I guess the prop wash would give you quite a bit more control . I'd like to hear from the experienced cub guys, thanks.